There are many situations which require cement structure to be repaired. Most notably, roadways frequently wear and degrade resulting in holes, cracks, etc.
One problem with some cement repair formulas is that they take too long to develop sufficient strength to permit resumed use of the cement structure. This can be a major problem if the cement structure is, for example, a heavily traveled road.
Rapid setting formulas have been used in the past. However, these formulas suffer from a variety of problems. For example, rapid setting cement formulas sometimes use ammonium phosphate which produces noxious ammonia gas when mixed.
Some cement formulas set too fast, allowing insufficient time to work the material into the desired location and form.